The Fish Is Huge: Forgetful Fish (Dandân)

Note: This article was translated from Chinese by AI and may contain errors. Read the original Chinese version.

Long time no see! I’m MiohitoKiri5474, and today I want to share a format with everyone: Forgetful Fish.

I vaguely remember running into this format a few years ago, probably because one day while browsing around scryfall or mtggoldfish, I saw a card that was inexplicably worth a bit of money: Dandân

Dandân, UU
Creature - Fish
This creature can’t attack unless defending player controls an Island.
When you control no Islands, sacrifice this creature.

After searching I found out there is a format built around Dandân: Forgetful Fish. Looking into it further, I found some of the cards are somewhat expensive and hard to collect. Never mind the other cards, just finding eight copies of the same printing of Dandân in Taiwan is difficult.

Yes, I have OCD, and every card has to be the same printing.

So I eventually let it drop. The whole deck is 64 cards not counting basic lands, and more than 50 of them would need to be sourced separately, which was a hassle just to think about.

Until one day a friend said he was going to place a CK order, and I had also just been burned by the Dandân SLD deck not long before (originally it could only be obtained at side events at tournament venues, and later some leftover stock was relisted and immediately sold out lol). Since I couldn’t get the whole SLD set, I figured I might as well build a Forgetful Fish deck myself… and so I ordered 7X cards from CK. I’ll get to why I bought so many later.

I finally finished building it recently, and played a bit with a friend and found it quite fun, so I wanted to share it with everyone.

Forgetful Fish Basics

First, let me introduce Forgetful Fish. It is a casual format whose core creature is Dandân, and unlike other formats, both players share the same mono-blue deck and graveyard.
The format was created by Nick Floyd in 1997, but it wasn’t widely known until Rhystic Studies introduced it in 2023. Together with the recent controversy around the SLD, the format got an even bigger push.

A Forgetful Fish deck is basically made up of 10 Dandânand 8 Memory Lapse, which is also where the name Forgetful Fish comes from, plus many blue instants, aiming to beat your opponent using the top of the library, the stack, and Dandân.

The rules are the same as most Magic constructed formats: starting at 20 life, seven-card hands, the player on the play doesn’t draw, maximum hand size of seven, drawing from an empty library loses the game, and so on. Besides the shared library and graveyard, in Forgetful Fish you can mulligan repeatedly until your opening hand contains at least two lands and two spells (you do have to reveal your hand to your opponent, of course), or mulligan following the standard mulligan procedure.

Also, opening hands are dealt alternately, like dealing poker cards, and if some effect makes the players draw cards at the same time, the active player goes first.

Finally, about controller/owner: for some effects (returning to hand), the card returns to the hand of its caster, while into your library or from your graveyard refers to the shared graveyard and library.

As for how to win, it’s basically hitting your opponent five times with Dandân, or locking things down so hard that your opponent has to draw from an empty library (though that should be extremely hard to pull off).

A standard decklist looks like this:
Decklist link

10x Dandân

 4x Accumulated Knowledge
 2x Brainstorm
 2x Dance of the Skywise
 2x Insidious Will
 8x Memory Lapse
 2x Metamorphose
 2x Mind Bend
 2x Mystical Tutor
 2x Predict
 2x Crystal Spray
 2x Ray of Command
 2x Supplant Form
 2x Unsubstantiate
 2x Vision Charm
 2x Diminishing Returns
 2x Mystic Retrieval

 2x Halimar Depths
18x Island
 2x Izzet Boilerworks
 2x Lonely Sandbar
 2x Mystic Sanctuary
 2x Remote Isle
 2x Svyelunite Temple
 2x Temple of Epiphany

Since this is a casual format, modifying the deck contents yourself is no problem after all, there are no tournaments anyway. Nick Floyd has probably iterated on it several times, especially since some of the newer cards were only released in the last decade (like Mystic Sanctuaryand Dance of the Skywise).

For example, I thought Mystical Tutorand Crystal Spraywere too expensive to buy, so I swapped them for Thought Scourand Magical Hack.

That’s also why I originally found a decklist that another player had tweaked, assumed it was the original version, and started buying cards according to it. Only after placing the order did I realize that several cards differed from what I remembered, so I later added another order, ending up with 7X cards in the end.

The War for the Top of the Library

In Forgetful Fish, I think the most important thing is controlling the top card of the library.

For example, Memory Lapsecounters a spell and puts it on top of the library, which means a player can counter the opponent’s spell onto the top of the library and then draw it into their own hand by any draw effect. You can also use things like Predictor Brainstormto wreck the top of the library your opponent has set up, or hand the junk cards in your hand to your opponent when they’re about to draw.

In a game against a friend, for example, I used Memory Lapseto counter his Dandânonto the top of the library and wanted to use Predictto gain two cards, but he got ahead of me by cycling Lonely Sandbarto wreck the top of the library, leaving me one card short.

”You don’t control a Mountain now? Then your Dandân dies”

Although the whole deck is mono-blue, that doesn’t mean there’s no removal.
…For example, I change all the rules text on your Dandânto Mountain.

Mind Bend
U, Instant
Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another.
For example: change “nonblack creature” to “nongreen creature”, or “Forestwalk” to “Islandwalk”. This effect doesn’t end at end of turn.

Since you don’t control a Mountain, by the rules you must immediately sacrifice Dandân.
The only ways to defend are to use Unsubstantiateto return Dandânto hand first, or to use Dance of the Skywiseto wipe its abilities first and save it for a turn.

As for whether a card can still have its text changed after it loses abilities, the answer is yes, because losing abilities doesn’t turn the whole card into a vanilla; the card’s own characteristics still include that text, it just isn’t taking effect.
Also, text-changing effects are in Layer 3 while adding and removing abilities (losing/gaining abilities) is in Layer 4, so even if Dandânhas its abilities wiped by Dance of the Skywise, it will still have its text changed by Mind Bend, and then in the cleanup step of that turn’s end step it loses the effect of Dance of the Skywiseand gets sacrificed.

I originally thought I could use Vision Charmto change the basic land types back to the corresponding ones to keep Dandânfrom being sacrificed, but after thinking about it, whether in response to Mind BendI cast Vision Charm, or after Mind Bendresolves I cast Vision Charm, there is a moment in between when Dandândoesn’t meet its survival condition and gets sacrificed.
But on the flip side, you can also use Vision Charmas a one-mana sweeper to wipe out every Dandânon the battlefield.

Conclusion

Forgetful Fish is very fun to play, and it can also help newer players build an understanding of the stack, or help them get to know and practice how to handle blue mirror matches.
In theory Forgetful Fish could be extended to any color, but I think none of them compare to mono-blue; frankly, other colors can’t change the top of the library as often as blue does, so they lose the fun of the shared library.

Although I’ve (more or less) finished the deck, I still feel it’s a pity I didn’t get that SLD set, and I really want that playmat too (curling up under the blanket biting my pillow). UG sells it, but they only ship to addresses in Europe.

And that set of Islands is really tempting. As an Island fanboy (?), not collecting a set would be letting myself down.

…That said, I’ve seen quite a few people on Twitter and Reddit run into misprints or shipping mishaps, and then I feel like not having ordered it is kind of fine.